The invention relates to a locking system for vehicular seats, in particular, for motor vehicle seats which can be slid longitudinally in the direction of travel. Locking systems for vehicular seats that can be fixed in selectable positions are described in DE 27 29 770 C2 wherein a stationary rail is provided with identical snap-in holes arranged in a row at equal intervals. Two bolts which are connected to the vehicular seat and engage with the rail can fall independently of each other into the snap-in holes. For safety reasons, such a locking system is designed such that at least one bolt can fall in each selectable seat position. If only one of the two bolts engages with one of the snap-in holes, the seat can be slid until the second bolt drops in. However, even then the seat is movable because a certain play between the bolt and the snap-in holes is needed to ensure that the bolt will drop into the snap-in holes. This play leads to an annoying chatter.